[fpc-devel] Can someone confirm if this is a bug? (ancestor in TWRiter.WriteProperty)

[Martin]

I am not very familiar with the code, so before reporting, I'd like to ask:

trunc\rtl\objpas\classes\writer.inc
procedure TWriter.WriteProperty(Instance: TPersistent; PropInfo: Pointer);

Imagine you a writing an Component, that does have an ancestor.
The same component should have
   property Foo: TPersistentChild read FFoo write FFoo;

You should end up in the following code: (line 1091 in recent (a few 
weeks) trunc )
// this is the last else, it's not a component, and it is not a collection
          else
            begin
            SavedAncestor := Ancestor;
            SavedPropPath := FPropPath;
            try
              FPropPath := FPropPath + PPropInfo(PropInfo)^.Name + '.';
              if HasAncestor then
                Ancestor := TPersistent(GetObjectProp(Ancestor, 
PropInfo)); 
              WriteProperties(TPersistent(ObjValue));
            finally
              Ancestor := SavedAncestor;
              FPropPath := SavedPropPath;
            end;
            end;
--------------------------------------
              if HasAncestor then
                Ancestor := TPersistent(GetObjectProp(Ancestor, 
PropInfo)); 

sets the ancestor to a persitent object

Now if TPersistentChild  itself has
  property Some: TComponent

then you end up again in TWriter.WriteProperty  writing a tclass property

    tkClass:
      begin
        ObjValue := TObject(GetObjectProp(Instance, PropInfo));
        if HasAncestor then
        begin
          AncestorObj := TObject(GetObjectProp(Ancestor, PropInfo));
          if Assigned(AncestorObj) then
            if Assigned(ObjValue) and
              (TComponent(AncestorObj).Owner = FRootAncestor) and
              (TComponent(ObjValue).Owner = Root) and
              (UpperCase(TComponent(AncestorObj).Name) = 
UpperCase(TComponent(ObjValue).Name)) then
              AncestorObj := ObjValue
//            else
//              AncestorObj := nil;
        end else
          AncestorObj := nil;


and this code assumes that the ancestor is a TComponent, but as seen 
before, the ancestor is not.


Shall I report a bug, or do I miss understand something?
(is there a workaround?)

Martin